Visualization of C7‐T1 on Portable Lateral Cervical Spine Radiographs Using a Lead‐lined Acrylic Filter

Abstract

Objective: To determine whether lead‐lined acrylic cervical filters can improve the quality of portable lateral cervical spine (c‐spine) radiographs for trauma patients. Methods: Twenty trauma patients who required portable c‐spine x‐rays had these taken with a lead filter attached to the collimator of the portable x‐ray machine to improve penetration and visualization of lower cervical structures without overpenetrating upper cervical structures. The radiographs of these patients were compared with the first portable c‐spine radiographs without filters for 20 controls matched for gender and injury severity. The comparison of radiographs was done by an experienced emergency physician and a neuroradiologist blinded to whether the filter was used. Results: The two groups were similar for demographic and clinical characteristics. There was a significant improvement in the ability to visualize the C7‐T1 level for the filter group compared with the control group (65% vs 30%, p < 0.05). Agreement between the physicians was excellent (kappa = 0.79, 95% CI = 0.60‐0.99). Conclusions: Lead‐lined acrylic filters improve the ability to visualize the lower c‐spine in trauma patients. © 1995 Society for Academic Emergency Medicine